Multiscale associations between global surface temperature anomaly and El Niño-Southern Oscillation

The El Niño-Southern Oscillation (ENSO) involves sea surface temperature and atmospheric variations in the eastern equatorial Pacific. This study integrates wavelet transform with Pearson correlation coefficient (PCC) to create a multiscale similarity measurement. The approach captures varying durations and frequencies, analysing transient, non-periodic, and non-stationary signal characteristics. Using global surface air temperature (SAT) data, we assess ENSO's impact on the global climate at various time scales, underscoring the importance of multiscale decomposition by comparing correlations among ENSO outer nodes over different scales.